Im kinda on a budget and I've been hearing alot great things about Fi. I want to get two 15's but i dont know which ones i should get. How much difference is there b/w the three?
A 10" woofer has 78.5 sqin of surface area. A 12" woofer has 113.04 sqin of surface area. A 15" woofer has 176.625 sqin of surface area. A 18" woofer has 254.34 sqin of surface area.
The larger you go, the more spl you will get with any given amount of power. But, you will tend to lose a flat linear response the larger you go. This is just a general statement tho. There are many great sounding 15"s and 18"s. You must also consider that wiring subs in parallel increases the systems overall efficiency. So, even tho 2 12"s have less surface area then one 18", if the 12's are wired in parallel into a lower impendence, they might not need as much power to reach full excursion. Thus, louder then the 18' with the same given power.